Hallo,
I’m back with a little question that came up while measuring used (old) batteries from 1,5 V up to12 V.
As I learned from books, the measuring of batteries with a voltmeter has one drawback: even if the battery is low, the measurement will show a pretty high voltage, because their is no proper load while measuring.
The reason for that is - as far as I know - the inner resistence of the source.
So I tried to do two different readings:
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I measured a 1,5 Volt battery AA-size) at it’s both ends. Result: 1,58 Volt on the HPS 140.
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Then I inserted in the outer circuit an addtional resistor of 10 Ohm in a row with the HPS 140. Result: exactly the same value. I’m pretty perplexed.
I tried it with many different resistor types and different battery types (up to 12 V). It was always the same voltage of the reading. In our example 1,58 all the time. Even with a resistor of 1 Ohm - nothing changed.
I’m pretty surprised by the result. I cannot believe it.
Is there some mistake I’m making? Or is it mistake of thinking?
Cheers
carissima